age class vs social class

age class and social class both are nouns.

Word	Noun	Adjective	Verb	Adverb
age class	Yes	No	No	No
social class	Yes	No	No	No

As nouns, social class is a hypernym of age class; that is, social class is a word with a broader meaning than age class:

age class: people in the same age range
social class: people having the same social, economic, or educational status

Other hypernyms of age class include class, socio-economic class, stratum.

age class (noun)	social class (noun)
people in the same age range	people having the same social, economic, or educational status